Whipple's disease is a disease which manifests itself in a variety of forms. The most classic form is that of a fever with chronic diarrhea leading to weight loss, but this disease is also capable of giving rise to chronic articular symptoms, cerebral symptoms with dementia and also cardiac symptoms, particularly endocarditis with negative hemoculture.
Since it was first described in 1907, Whipple's disease has been understood to involve the existence of a bacterium associated with “intestinal lipodystrophy” due to the observation of numerous microorganisms after the silver staining of a mesenteric ganglion (Whipple, Bull. John Hopkins Hosp. 1907; 18: 328–391). Demonstration of the non-specific PAS-positive (PAS=periodic acid-Schiff) character of this bacterium and subsequent observations by electron microscopy confirm the presence of an intracellular bacterial species of Gram-positive structure (Chears et al., Gastroenterology 1961; 41: 129–138). The universal molecular tool 16S rRNA made it possible to confirm this hypothesis, specifying the phylogenic taxonomy of this novel bacterial species and assigning to it the provisional name Tropheryma whippelii to evoke the idea of intestinal malabsorption and to honor the discoverer of the complaint (Relman et al., N. Engl. J. Med. 1992; 327: 293–301). The direct sequencing of 721 bases of an amplified fragment from a biopsy of one patient's small intestine (Wilson et al., Lancet 1991; 338: 474–475) and then from another patient's ganglion (Wilson et al., ASM News 1992; 58: 318–321) confirms the novelty of the bacterial species associated with Whipple's disease. The sequencing by Relman et al. (op. cit.) of 1321 bases in one sample, representing 90% of the gene, and of a fragment of 284 bases in four other patients made it possible to confirm that the bacterial species associated with Whipple's disease represented a novel species, and to specify its taxonomic position in the phylum of the actinomycetes, i.e. the bacteria of Gram-positive structure with a high content of guanosine plus cytosine, representing a new branch relatively close to two species known in human pathology, namely Actinomyces pyogenes and Rothia dentocariosa. 
The disease is currently diagnosed by microscopic observation, after staining, of a smear obtained from a biopsy, or by amplification and sequencing of the universal genetic tool 16S rRNA (Relman et al., op. cit.).
Hitherto, it has in fact been impossible to isolate and cultivate the bacterium responsible for Whipple's disease in a manner suitable for performing serological tests.
Contrary to all expectation, the Applicant has developed a method of culturing the bacterium responsible for Whipple's disease.